Comparing Alexa with Google Analytics is like comparing apple and oranges.
The number of visits calculation from Google Analytics, comes from the execution of a JavaScrip tag on your webpages, each time a visitor load one of your pages. There are catches (sometime javaScript doesn't execute or JavaScript is not enabled in the browser), but overall estimations are pretty accurate.
The number of visits calculated by Alexa is instead based on an extrapolation of the visits recorded by people that have the Alexa toolbar installed in their browser. Since the amount of people browsing with the Alexa toolbar is very small a (fraction of a percent). These estimations are largely inaccurate (especially for low traffic websites as the statistic base of visitors doesn't include a large amount of visitors with the Alexa toolbar)
If you want to compare yourself with a competitor you can use Alexa, in a relative way without taking in consideration the absolute values, but you cannot compare directly Alexa and Google Analytics figures. 2.4k views · View 5 Upvoters
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